For adolescents (ages 12-24), use of marijuana and other drugs, alcohol, and tobacco is prevalent in the United States and associated with risks for negative outcomes. Although numerous initiatives have encouraged provision of screening for substance use and appropriate anticipatory guidance or brief interventions (SBI) in primary care settings, available research indicates adherence to these recommendations is inconsistent at best. Adoption of specific organizational policies procedures to support and monitor provision of SBI is among the major determinants of adherence. Currently, recommended SBI protocols differ in terms of their resource-use and other requirements for primary care settings. Parallel differences among new technologies introduced in other health care context have been shown to both influence organizational adoption and practitioner adherence. This study will apply a set of hypotheses derived from emerging models of diffusion of innovation to SBI adoption in primary care settings for adolescents. These hypotheses will be tested in a national telephone survey of the clinical directors of Community Health Centers and School Based Health Centers in 60 market areas (n=300). Our specific study aims are to: 1.Describe variations in adoption of protocols to support and monitor provision of SBI for marijuana and other drugs, alcohol, and tobacco to adolescents in public sector primary care settings; 2. Model the organizational and contextual factors associated with adoption of policies and procedures to support and monitor provision of substance use SBI in these settings; 3.Examine the characteristics of SBI protocols and dissemination strategies that increase clinical directors intentions to adopt marijuana and other drugs SBI protocols for adolescents in public sector primary care settings. Hypotheses will be tested using multivariate regression techniques. It is anticipated that SBI approaches with greater relative advantage, compatibility, complexity, and "observability" are more likely to be adopted, and that settings with more organizational and external supports for these innovations will show greater levels of adoption. Based on our modeling of prior adoption determinants and assessments of alternative SBI approaches, it will be possible to identify dissemination strategies that are most likely to be successful as substance use SBI evidence-based guidelines are further developed.